This project is aimed at a study of certain aspects of body composition in patients with diabetes mellitus. Lean body mass is estimated from potassium-40 assays, and certain clinical and laboratory data are obtained. These include duration of diabetes, type of treatment, presence or absence of complications, urine albumin, serum protein levels, etc. Results from these subjects are to be compared with those from normal (non-diabetic) subjects matched for age, stature, and sex.